Wednesday, December 22, 2010
Nembo Super 32: Inverted engine, anyone?
Why would you build a motorcycle that’s fitted with a 2000cc three-cylinder engine that’s fitted upside down? Yes, that’s right – an inverted engine, with the cylinder heads facing the asphalt. ‘I’ve chosen this particular engine architecture for both functional and aesthetic reasons,’ says Daniele ‘Titus’ Sabatini, owner, project leader and chief designer of the Nembo Super 32. ‘In current naked sportbikes, the engine is often hidden and in the case of liquid-cooled engines, practically soulless. It pains me to see the engine smothered under frames and plastic components. So, I thought that a good way to use an updated air-cooled engine in a contemporary naked sportbike would be to invert the engine!’ he adds.
Sabatini tells us that ‘inverted’ engines aren’t new and that they were used in various combat aircraft in WWII. However, the challenge was to use such an engine in a motorcycle, in a way that would combine form and function and that would keep things interesting.
‘I wanted to build a high-performance big-bore motorcycle, which would look ‘new’ but which would still have a classic and timeless beauty. The bike would have to be built with high quality metal and carbonfibre components and would be very light,’ says Sabatini, adding that he wanted to create a bike that looked like a proper motorcycle and not like a manga robot. Ahem.
‘Inverting the engine allowed me to achieve these results. The Super 32 is built around the engine, where the engine, by means of a super-compact crankcase that’s placed over the cylinders and the heads, works as the chassis, while the heads and cylinders do not participate in structural functions in any way,’ he says.
Sabatini claims his naturally aspirated inverted engine – the Super 32 Rovescio – complies with Euro 3 emissions norms and can be built in displacements ranging from 1850cc to 2100cc, with power outputs between 160-250bhp. The engine works as a fully stressed member, but the Super 32 also utilizes steel tube trellis frame components at the front, while the swingarm is made of carbonfibre. The bike’s dry weight ranges between 140-155kg, depending on the materials used and options chosen.
‘The Nembo Super 32 is at its early stages of development. The first two 1814cc prototypes are scheduled to be track tested in February 2011, after which I’ll start producing a small series of Super 32s, fitted with a 1925cc inverted engine,’ says Sabatini. ‘The bike is handcrafted in Italy by a highly specialized Italian crew and only a fifth of its components (wheels, brakes, forks and tyres) are bits that haven’t been designed and built by Nembo,’ he adds.
According to its builder, the Super 32 is the only bike in the world fitted with an inverted engine. ‘The bike’s architecture achieves our main goals of mass centralization, chassis elimination, extreme lightness (considering the use of a large displacement engine), great handling, and beauty,’ he says. And why not. We quite agree with most of what Sabatini says, and we think his machine is quite beautiful – not just to look at, but also as in terms of sheer innovation and engineering.
Nembo Super 32: Tech Specs
Front Suspension: 50mm USD fork with dual-rate springs, adjustable preload, rebound and compression damping
Rear Suspension: Air suspension system with adjustable preload and rebound and compression damping
Brakes: Brembo, 320mm discs, four-piston radial-mount calipers (front), single 220mm disc, two-piston caliper (rear)
Engine (prototype): Four-stroke, air/oil-cooled, three-cylinder, 1814cc, SUHC, 2-valves-per-cylinder, 160bhp at 7,000rpm
Engine (production): Four-stroke, air/oil-cooled, three-cylinder, 1925cc/2097cc, SUHC, 2-valves-per-cylinder, 200bhp/250bhp at 7,500rpm/8,000rpm
Visit the Nembo website here